240 
R. toxopleura, Tate (nom. mut.), Trans. Roy. Soc. 8. Aust. 
XVITI., 1893, p. 200. 
Ff. nivea is referred by Tryon to Schwartziella, whilst he places 
f. lirata under Rissoina (sensu stricto). I am afraid that either 
I do not appreciate the differences between these sections or that 
Tryon had no personal knowledge of the species, as I have no 
hesitation in attaching R. lirata to R. nivea. If there be any 
question as to its sectional position, it should be as to its refer- 
ence to Zebinella. 
The type of R. nivea was collected at Port Lincoln, and the 
species was listed for South Australia by Angas, P.Z.S., 1878, p. 
867; whilst the specimens which served him for his description 
and figure of &. lirata, published two years later, were supplied 
by me. The descriptions of the two are essentially identical, 
whilst my cotypes of #. lirata agree thoroughly with Schwartz’s 
figure of R. nivea. 
In ignorance of the invalidity of Angas’ name I changed it, as 
above indicated, because it had previously been employed by 
Gould in 1861. 
Distribution.—This species is common in shell-sand in St. 
Vincent Gulf, the type is from Port Lincoln, and I have taken it 
at Denial Bay on the west coast of South Australia. It has 
been sent to me from King George Sound, West Australia. 
Tenison-Woods records it for Tasmania. 
Rissoina spirata, Sowerby. 
References.—R. spirata, Sowerby, Genera Shells, 1820-24, t. 
208, fig. 2; Schwartz, Rissoiden, 1860, p. 101, f. 69; Reeve, 
Tcon. Conch., f. 17 (bad) ; Tryon, Man. Conch. IX., p. 388, t. 
58, £. 29 (copied from Reeve). 
Many synonyms are included by Tryon under R. spirata; of 
these R. d’Orbignyi, which, judging from Schwartz’s figure of it, 
is inseparable. R. d’Orbignyi has been listed as a South Aus- 
tralian shell by Angas, but in 1893 I referred it to &. spirata. 
The specimens which I attribute to A. syirata have the exact 
outline and size corresponding with Schwartz’s figure, but instead 
of the anterior whorls having the axial ornamentation replaced 
by spiral strie they present a gradual decadence in the strength 
of the costation, and though it is faint on the body-whorl, yet it 
is more conspicuous, even there, than the microscopic spiral 
striation. 
Tryon refers R. spirata to Morchiella, but it offers, at any rate 
in our Southern Australian examples, no essential differences 
from Rissoina (s.s.); it is thus a connecting link between 
the two sections. A smooth and small kind also occurs. The 
- Morchiella-state may possibly be exhibited in each of the sub- 
